3.9

M3.9 Earthquake 128 km W of Nikolski, AlaskaFebruary 11, 2025

2025-02-11 17:36:04 UTC (2025-02-11) · approx. 6:36 AM UTC-11 local

MagnitudeM3.9(mb)
Time17:36 UTC6:36 AM UTC-11
Depth68.1 kmshallow crustal
Coordinates52.774°, -170.751°
Felt byNo felt reports
Status✓ Reviewed by USGS

On February 11, 2025 at 17:36 UTC, a magnitude 3.9 shallow crustal earthquake struck 128 km W of Nikolski, Alaska, at a depth of 68.1 km and coordinates 52.7741°, -170.7510°.

Physical scale: An earthquake of magnitude 3.9 releases seismic energy equivalent to roughly 11 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 296 m — a useful intuition for the size of the slip patch on the fault.

Map showing earthquake epicenter at 52.77°, -170.75°

Earthquake Details

Magnitude
3.9 mb
Depth
68.1 km
shallow crustal
Location
52.7741°N
-170.7510°E

Technical Information

Event ID
us7000petj
Event Type
earthquake
Status
✓ Reviewed
Significance
234
Stations Used
38
Azimuthal Gap
165.0°
Min Station Distance
0.454°
RMS Residual
0.84 sec
Last Updated
2025-04-26 14:47:11 UTC

Common Questions

How strong was the magnitude 3.9 earthquake near Nikolski, Alaska?

The magnitude 3.9 earthquake that struck 128 km W of Nikolski, Alaska on February 11, 2025 at 17:36 UTC had a depth of 68.1 km. For context, this was a minor earthquake typically detected only by instruments.

Were there aftershocks?

Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.9 earthquakes can continue for several days and gradually diminish over time.

Understanding This Data

Magnitude 3.9 earthquakes are typically only recorded by instruments.

Learn more about magnitude →

Authoritative source: USGS event page (event ID: us7000petj). All scientific values on this page are sourced verbatim from the USGS feed.

Cite this page: EarthquakeTracker.org. (2025, February 11, 2025). M3.9 Earthquake 128 km W of Nikolski, AlaskaFebruary 11, 2025. Retrieved April 26, 2025 from https://www.earthquaketracker.org/earthquakes/event/us7000petj/